Should there be an inverse stft in DSP.jl?

Yeah, it would be useful to have istft. There’s an implementation in @jongwook’s MusicProcessing.jl but it’s somewhat audio-specific (it uses the samplerate-aware buffer types from SampledSignals). There was also a PR to DSP.jl with an implementation - looks like it’s maybe just stalled?

It could probably use a review and rebase,